Sodium borohydride → (3-Chloro-4-methylsulfanyl-phenyl)-hydroxy-acetic acid ethyl ester

A solution of (3-chloro-4-methylsulfanyl-phenyl)-oxo-acetic acid ethyl ester (3.93 g, 15.19 mmol) in methanol (30 mL) was cooled to 0° C. and then treated with sodium borohydride (530.9 mg, 14.03 mmol). The reaction mixture changed from yellow to colorless. The mixture was stirred for 15 min and then quenched with a 1 N aqueous hydrochloric acid solution (10 mL). The resulting reaction mixture was then extracted with methylene chloride (2×30 mL). The combined organic layers were washed with a saturated aqueous sodium chloride solution (1×30 mL), dried over sodium sulfate, filtered, and concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 230-400 mesh, 9/1 then 4/1 hexanes/ethyl acetate) afforded (3-chloro-4-methylsulfanyl-phenyl)-hydroxy-acetic acid ethyl ester (1.43 g, 38%) as a white solid: mp 56-57° C.; EI-HRMS m/e calcd for C11H13ClO3S (M+) 260.0273, found 260.0276.

1. customquenched with a 1 N aqueous hydrochloric acid solution (10 mL)
2. customThe resulting reaction mixture
3. extractionwas then extracted with methylene chloride (2×30 mL)
4. washThe combined organic layers were washed with a saturated aqueous sodium chloride solution (1×30 mL)
5. dry with materialdried over sodium sulfate
6. filtrationfiltered
7. concentrationconcentrated in vacuo

ORD record

ord-9b2f52a1559e4437a130afc0b4f94fdb

Source dataset

uspto-grants-2001_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06320050B1